Topologically Mixing Properties of Multiplicative Integer Systems

Motivated from the study of multiple ergodic average, the investigation of multiplicative shift spaces has drawn much of interest among researchers. This paper focuses on the relation of topologically mixing properties between multiplicative shift spaces and traditional shift spaces. Suppose that $\mathsf{X}_{\Omega}^{(l)}$ is the multiplicative subshift derived from the shift space $\Omega$ with given $l > 1$. We show that $\mathsf{X}_{\Omega}^{(l)}$ is (topologically) transitive/mixing if and only if $\Omega$ is extensible/mixing. After introducing $l$-directional mixing property, we derive the equivalence between $l$-directional mixing property of $\mathsf{X}_{\Omega}^{(l)}$ and weakly mixing property of $\Omega$.